Preparation And Application Of Poly(Amine-epichlorohydrin) Modified Anion-exchange Resin

With the development and innovation of technology,ion chromatography(IC)has become an indispensable analytical technique in the fields of environment,industry,agriculture,biomedicine and food with advantages of fast,convenient,selective and sensitive.Simultaneously,the increasing complexities of samples put forward higher requirements for the separation of sample pretreatment materials and stationary phases.Therefore,the development of novel adsorption and separation materials is of significant importance.In chapter one,it was introduced that the IC development,matrices and applications of IC stationary phase,which mainly focused on the synthesis methods,modification methods and applications of organic polymer matrices.Meanwhile,the research progress and applications of poly(amine-epichlorohydrin)were briefly introduced.In chapter two,a novel anion-exchange resin was successfully synthesized based on polystyrene-divinylbenzene microspheres and poly(amine-epichlorohydrin)cationic polyelectrolyte.Epichlorohydrin and methylamine as monomers were used to prepare quaternized cationic polyelectrolyte and hyperbranched layers.Scanning electron microscopy(SEM),nitrogen adsorption/desorption method(BET),Fourier transform infrared spectra(FTIR)and elemental analysis were utilized to characterize the surface morphology,pore structure and chemical composition of bare microspheres and modified microspheres.The result showed that poly(amine-epichlorohydrin)was successfully modified on the surface of microspheres with a number of hydroxyl groups and amine groups.The surface morphology and monodispersity of microspheres were hardly changed through the modified process,while the porous structure was changed remarkably.The characterization and modification of microspheres demonstrated that poly(amine-epichlorohydrin)modified resins have potential applications for adsorption materials and chromatographic stationary phases.In chapter three,an ion chromatography method coupled with solid phaseextraction was established for the simultaneous determination of trace organic acids and inorganic anions in sodium carboxymethyl cellulose(CMC).In order to prevent CMC from contaminating analytical column,a self-packed solid phase extraction column packed with poly(amine-epichlorohydrin)modified resins was applied in sample pretreatment.An Ion Pac AS11-HC column was used as the analytical column for separation of glycolate,chloroacetate,chloride and sulfate with gradient elution of potassium hydroxide at a flow rate of 1.0 m L/min.Under the optimized chromatographic conditions,the linearity of the method was satisfactory over a concentration range of 0.5-150.0 mg/L with correlation coefficients of 0.9992-0.9999,and the limits of detection(S/N = 3)varied from 0.05 to 0.50 mg/L.The proposed method was successfully applied to the analysis of organic acids and inorganic anions in CMC samples.The recoveries ranged from 86.7%-109.0% with the relative standard deviations over the range of 0.32%-3.61%.The method offers a reliable application for the analysis of trace organic acids and inorganic anions in complex anionic cellulose.In chapter four,different times of hyperbranched reaction were performed on the poly(amine-epichlorohydrin)agglomerated resin to bulid quaternary ammonium groups.The exchange capacity of stationary phase could be controlled via hyperbranched layers.Combined with characterization of elemental analysis,the separation of common anionic anions was performed on the modified resins with different hyperbranched layers.Due to denser charged density and high hydrophilcity of poly(amine-epichlorohydrin),the modified stationary phase could separate common anions and polarizable anions in a short time with good column efficiency and stability.Finally,the contents of thiosulfate in water reducing agent samples were determined with the homemade column after the methodological investigation.